Biblio
Renewed focus on spacecraft networking by government and private industry promises to establish interoperable communications infrastructures and enable distributed computing in multi-nodal systems. Planned near-Earth and cislunar missions by NASA and others evidence the start of building this networking vision. Working with space agencies, academia, and industry, NASA has developed a suite of communications protocols and algorithms collectively referred to as Delay-Tolerant Networking (DTN) to support an interoperable space network. Included in the DTN protocol suite is a security protocol - the Bundle Protocol Security Protocol - which provides the kind of delay-tolerant, transport-layer security needed for cislunar and deep-space trusted networking. We present an analysis of the lifecycle of security operations inherent in a space network with a focus on the DTN-enabled space networking paradigm. This analysis defines three security-related roles for spacecraft (Security Sources, verifiers, and acceptors) and associates a series of critical processing events with each of these roles. We then define the set of required and optional actions associated with these security events. Finally, we present a series of best practices associated with policy configurations that are unique to the space-network security problem. Framing space network security policy as a mapping of security actions to security events provides the details necessary for making trusted networks semantically interoperable. Finally, this method is flexible enough to allow for customization even while providing a unifying core set of mandatory security actions.
Firewall is the first defense line for network security. Packet filtering is a basic function in firewall, which filter network packets according to a series of rules called firewall policy. The design of firewall policy is invariably under the instruction of security policy, which is a generic guideline that lists the needs for network access permissions. The design of firewall policy should observe the regulations of security policy. However, even for IPv4 firewall policy, it is extremely difficult to keep the consistency between security policy and firewall policy. Some consistency decision methods of security policy and IPv4 firewall policy were proposed. However, the address space of IPv6 address is a very large, the existing consistency decision methods can not be directly used to deal with IPv6 firewall policy. To resolve the above problem, in this paper, we use a formal technique to decide the consistency between IPv6 firewall policy and security policy effectively and rapidly. We also developed a prototype model and evaluated the effectiveness of the proposed method.
The growing adoption of IoT devices is creating a huge positive impact on human life. However, it is also making the network more vulnerable to security threats. One of the major threats is malicious traffic injection attack, where the hacked IoT devices overwhelm the application servers causing large-scale service disruption. To address such attacks, we propose a Software Defined Networking based predictive alarm manager solution for malicious traffic detection and mitigation at the IoT Gateway. Our experimental results with the proposed solution confirms the detection of malicious flows with nearly 95% precision on average and at its best with around 99% precision.
With the rapid development of Internet scale and technology, people pay more and more attention to network security. At present, the general method in the field of network security is to use NSS(Network Security Situation) to describe the security situation of the target network. Because NSSA (Network Security Situation Awareness) has not formed a unified optimal solution in architecture design and algorithm design, many ideas have been put forward continuously, and there is still a broad research space. In this paper, the improved LSTM(long short-term memory) neural network is used to analyze and process NSS data, and effectively utilize the attack logic contained in sequence data. Build NSSF (Network Security Situation Forecast) framework based on NAWL-ILSTM. The framework is to directly output the quantified NSS change curve after processing the input original security situation data. Modular design and dual discrimination engine reduce the complexity of implementation and improve the stability. Simulation results show that the prediction model not only improves the convergence speed of the prediction model, but also greatly reduces the prediction error of the model.
Verification code recognition system based on convolutional neural network. In order to strengthen the network security defense work, this paper proposes a novel verification code recognition system based on convolutional neural network. The system combines Internet technology and big data technology, combined with advanced captcha technology, can prevent hackers from brute force cracking behavior to a certain extent. In addition, the system combines convolutional neural network, which makes the verification code combine numbers and letters, which improves the complexity of the verification code and the security of the user account. Based on this, the system uses threshold segmentation method and projection positioning method to construct an 8-layer convolutional neural network model, which enhances the security of the verification code input link. The research results show that the system can enhance the complexity of captcha, improve the recognition rate of captcha, and improve the security of user accounting.

